Patent · US Expired

Method for making organic polycarboxylic acids

US4128574A · kind A · utility

27Cited by
1References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 4, 1976
Grant dateDec 5, 1978
Priority date
Expiry dateOct 4, 1996

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07D209/48
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A method is described for making organic polycarboxylic acids or anhydrides, such as aromatic ether bis(phthalic acid)s, based on a cyclic imide-cyclic anhydride exchange reaction at elevated temperatures in the presence of water. In addition to making organic polycarboxylic acid, organic imides are also generated.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.